1998545455 has 16 divisors (see below), whose sum is σ = 2441918304. Its totient is φ = 1569922560.

The previous prime is 1998545447. The next prime is 1998545467. The reversal of 1998545455 is 5545458991.

It is not a de Polignac number, because 1998545455 - 2³ = 1998545447 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1998545396 and 1998545405.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 70795 + ... + 94915.

It is an arithmetic number, because the mean of its divisors is an integer number (152619894).

Almost surely, 2^1998545455 is an apocalyptic number.

1998545455 is a deficient number, since it is larger than the sum of its proper divisors (443372849).

1998545455 is a wasteful number, since it uses less digits than its factorization.

1998545455 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24426.

The product of its digits is 6480000, while the sum is 55.

The square root of 1998545455 is about 44705.0942846562. The cubic root of 1998545455 is about 1259.6155405095.

It can be divided in two parts, 1998545 and 455, that added together give a triangular number (1999000 = T₁₉₉₉).

The spelling of 1998545455 in words is "one billion, nine hundred ninety-eight million, five hundred forty-five thousand, four hundred fifty-five".